Two cases of mild IgM-negative measles in previously vaccinated adults, the Netherlands, April and July 2011

Area of Science:

• Immunology
• Virology
• Public Health

Background:

• Measles is a highly contagious viral illness.
• Vaccination is the primary strategy for measles prevention.
• Understanding disease presentation in vaccinated individuals is crucial for transmission modeling.

Observation:

• Two fully vaccinated adults in the Netherlands presented with mild measles symptoms.
• These individuals exhibited a lack of specific antibody responses typically seen in measles infection.
• Low levels of detectable virus were observed in these cases.

Findings:

• The clinical presentation was significantly milder than typical measles.
• The absence of a robust IgM antibody response was noted.
• Reduced viral shedding likely contributed to a lower risk of transmission.

Implications:

• Vaccinated individuals experiencing breakthrough infections may have reduced contagiousness.
• This finding has implications for measles surveillance and control strategies.
• Further research is needed to quantify transmission risk from vaccinated individuals.